重组毕赤酵母高密度发酵表达H5N1禽流感病毒糖蛋白

在10L发酵罐中,对高致病性禽流感病毒H5N1糖蛋白HA1在重组毕赤酵母中的表达发酵工艺进行了研究。通过分批补料培养方法探讨不同培养温度、诱导温度、补料方式、微量元素等因素对菌体的生长以及重组蛋白表达和活性的影响。结果表明,菌种培养和诱导温度均为25oC时,菌体的生长、分泌表达量和与广谱中和抗体的反应活性较好;微量元素是影响重组HA1蛋白生物活性的重要因素;通过优化高密度发酵工艺,H5N1病毒糖蛋白HA1在发酵罐中的表达量比摇瓶培养提高10.5倍,达到约120mg/L,为大规模制备高致病性禽流感病毒的HA1蛋白奠定了基础

电流密度和温度对VRB性能的影响

利用千瓦级全钒液流电池（VRB）模块，考察了电流密度和温度等因素对VRB输出性能的影响。在1．000～1．550V的单体电池工作电压区间内，充电电流密度对容量的影响比放电电流密度大。随着温度从25℃降低至-5℃，VRB的极化从20mV／20mA·cm^2增加到40mV／20mA·cm^2；以80mA／cm^62和40mA／cm^2循环时，能量效率降低率分别约为0．32％／℃和0．06％／℃

电流密度和温度对VRB性能的影响

利用千瓦级全钒液流电池（VRB）模块，考察了电流密度和温度等因素对VRB输出性能的影响。在1．000～1．550V的单体电池工作电压区间内，充电电流密度对容量的影响比放电电流密度大。随着温度从25℃降低至-5℃，VRB的极化从20mV／20mA·cm^2增加到40mV／20mA·cm^2；以80mA／cm^62和40mA／cm^2循环时，能量效率降低率分别约为0．32％／℃和0．06％／℃

DISTRIBUTION AND SOURCE of POLYCYCLIC AROMATIC HYDROCARBONS IN THE SURFACE SEDIMENTS of QUANZHOU BAY,CHINA

采用气相色谱-质谱联用(gC-MS)方法,对泉州湾表层沉积物中16种优先控制多环芳烃(PAHS)进行定量分析,采用lMW/HMW、bAA/(bAA+CHr)、InP/(InP+bgP)、PPI等特定比值对PAHS来源进行分析.结果表明,沉积物中PAHS的总含量在182.8—721.1 ng.g-1之间,以3—5环为主;PAHS在表层沉积物中的含量分布总体呈现为泉州湾南岸高于北岸、内湾高于外湾;沉积物中PAHS主要来自高温不完全燃烧.与国内外其它海域相比,泉州湾PAHS处于中等污染水平,该区域表层沉积物中的PAHS对生物不存在明显的毒性效应,但具有潜在的毒副作用.The concentrations of 16 polycyclic aromatic hydrocarbons(PAHs) in the surface sediments of Quanzhou Bay,China,were measured with gas chromatography-mass spectrometry(GC-MS).Source-specific PAHs indexes,including LMW/HMW,BaA/(BaA+Chr),InP/(InP+BgP) and Ppi,were used to identify the potential sources of PAHs in this region.The total contents of PAHs in the sediments were in the range of 182.8—721.1 ng · g-1,which were dominated by PAHs of 3—5 rings.The concentration of PAHs in the Bay was higher in the south bank than in the north bank,and higher in the inner bay than in the outer bay as well.The indexes of source identification indicated that incomplete combustion was the dominant source of PAHs in this study.The pollution of PAHs in the Bay was moderate compared with other regions in the world.PAHs in the surface sediments in this area would not cause remarkably negative effects on marine organisms,but potential negative effects should not be overlooked.海洋公益性行业科研专项(No.200705029)资

Synthesis and Characterization of Pd(dppm)_2 and Its Catalytic Properties

合成了以双齿膦dppm为配体的金属配合物Pd(dppm)2,通过元素分析、红外光谱、热分析、光电子能谱、多晶粉末衍射等技术对该配合物的结构进行表征;用该配合物制备负载型Pd催化剂,并对其催化性能进行了研究,表明该催化剂对CO催化氧化成CO2的反应具有较好的催化效果.The title complex,Pd(dppm)_2 was prepared by treatment of a solution of PdCl_2 with bis(diphenylphosphino)methane (dppm) and NH_2NH_2·H_2O in nitrogen atmosphere,with yield at 81.2 percent.As a new palladium complex with ligand of phosphine,Pd(dppm)_2 was characterized by elementary analysis,IR spectra,XPS spectra,X-ray powder analysis,as well as thermal analysis.A plane square structure of the complex was supposed.The IR and XPS measurements showed that the state of Pd in the complex of Pd(dppm)_2 was in between zero- and +2 state,and Ph-P-Pd-P-Ph hyperconjugation was found in the complex.Pd(dppm)_2/γ-Al_2O_3 catalyst was prepared by solvated metal atom impregnation (SMAI) method.The result of activity assay indicated that the catalyst of Pd(dppm)_2 supported onγ-Al_2O_3 with high dispersion showed high catalytic activity for the oxidation of carbonmonoxide,with CO conversion reaching 100% at 75℃ and GHSV=30 000 mL(STP)·h~(-1)·g~(-1),with good stability during 19 h of reaction operation.The Ph-P-Pd-P-Ph hyperconjugation enlarge the dislocalization scope of the electron cloud,which may be an important reason that Pd(dppm)_2/γ-Al_2O_3 catalyst exhibited higher activity for CO oxidation at low temperature than that of PdCl_2/γ-Al_2O_3 catalyst at the same experimental condition.福建省自然科学基金(F0210010);; 厦门大学校级自选课题基金资

佛坪国家级自然保护区大熊猫与潜在捕食者的时空动态

了解同域分布物种的行为活动在空间和时间上的分化,从群体行为上判断其生态位分化,是揭示其共存机制的重要途径。为了探明秦岭大熊猫(Ailuropoda melanoleuca)与同域分布的金钱豹(Panthera pardus)、黄喉貂(Martes flavigula)和豹猫(Prionailurus bengalensis)3种潜在捕食者的日活动节律、时空生态位及共存机制,于2017年1月—2019年12月在陕西佛坪国家级自然保护区利用红外相机技术开展监测。相关监测数据采用核密度估计、重叠指数和空间相关系数进行分析,结果表明:大熊猫日活动节律以昼间活动为主; 金钱豹和黄喉貂的日活动节律也为昼间活动模式,与大熊猫日活动节律重叠指数很高,且在昼间的活动强度高于大熊猫; 豹猫为典型夜间活动模式,与大熊猫日活动节律重叠指数较低。大熊猫与金钱豹的空间分布重叠程度很低,而黄喉貂和豹猫与大熊猫的空间重叠程度很高。综合时间和空间重叠程度,黄喉貂是佛坪国家级自然保护区大熊猫所面临的最具威胁的潜在捕食者。以上结果有助于综合评价秦岭野生大熊猫所面临的潜在捕食压力,为大熊猫种群保护与复壮提供科学依据